| Abstract: | DSM has developed a new foaming technology based on carbon dioxide released via a controlled chemical reaction through catalyzed decarboxylation of SMA, a copolymer of Styrene (S) and maleic anhydride (MA). This carbon dioxide is thus used as an environmentally friendly blowing agent to generate intrinsically foamed SMA-based materials. The modulus of the foam exceeds by far (factor of 2–3) the modulus of common thermoplastic foams based on e.g. PS. The tensile strength is also higher (10%). This opens up many opportunities for SMA foams in structural applications. One example is roofliners. SMA has also been successfully applied as a chemical blowing agent (e.g. in combination with ABS) for the production of a high-density foam on an injection moulding machine or an extruder. In this paper the chemical background, processing, properties and some applications of intrinsically foamed SMA will be discussed. |
